I think this won't pose any problem as it is the 512x512 image you give on submission which is used.
–
GeoffroyApr 18 '12 at 7:43

The exact guideline is stated below, but keep in mind... If you are considering added the word "Retina" into the high-res icon, I advise against it. The user is USUALLY aware that they have a retina device and don't need a constant reminder of it on their home screen. If this is not your intention please disregard.
–
0x7fffffff♦Apr 18 '12 at 8:39